Catheter assembly

ABSTRACT

A catheter assembly including a catheter hub being connectable to a device for the infusion or withdrawal of fluids; a hollow extension tube connected at its distal end to the catheter hub, the extension tube connectable at its proximal end to a device for infusing fluid into the chamber within the catheter hub; a valve assembly disposed within the chamber of the catheter hub having a first valve member and a second valve member preventing the flow of fluid through the chamber to or from the proximal end of the catheter hub. A needle guard assembly is also provided.

CROSS-REFERENCE TO RELATED APPLICATION

This is a continuation of co-pending application Ser. No. 14/890,419,filed Nov. 10, 2015, which is a national stage application ofInternational Application No. PCT/EP2014/067573, filed Aug. 18, 2014,which claims priority to GB 1314953.9, filed Aug. 21, 2013, GB1315401.8, filed Aug. 29, 2013, CN 201310527778.3, filed Oct. 31, 2013,and CN 201320679130.3, filed Oct. 31, 2013, the contents of which areexpressly incorporated herein by reference.

FIELD OF ART

The present invention relates to a catheter assembly, in particular toan intravenous catheter assembly.

BACKGROUND OF THE INVENTION

Intravenous (IV) catheters are used to access a vein of a patient, inparticular for the provision of fluids to the patient or the removal offluid, especially blood, therefrom. The IV catheter can be primed with asterile solution to remove air from the device prior to puncturing thepatient. This reduces the risks of the patient developing an airembolism.

An IV catheter assembly comprises a catheter extending from the distalend of a catheter hub. A needle extends through the catheter hub and thecatheter, such that the sharpened tip of the needle extends beyond thedistal end of the catheter. A typical procedure for insertion of thecatheter into the vein of the patient requires the healthcare worker toinsert the sharpened needle tip and catheter into the patient to locatethe vein. Once the needle tip is located in the vein, the healthcareworker manually forwards the catheter into the vein by sliding thecatheter along the shaft of the needle in the distal direction. Once thecatheter is properly located in the vein, the needle is withdrawn. Thecatheter is then secured by taping the catheter hub to the skin of thepatient. The vein may then be accessed for the infusion or removal offluids through the catheter hub and the catheter.

To control the flow of fluids through the catheter and the catheter hub,in particular to prevent blood leaving the vein through the catheter, itis known to provide a valve in the catheter hub.

A device for the drainage or infusion of liquids from or to a patient isdisclosed in EP 0 268 480. In one embodiment, the device comprises acatheter hub having a catheter extending therefrom. The catheter hub isprovided with a flexible valve therein for controlling the flow of fluidthrough the catheter hub. A valve opener is provided to open the valve,when fluid is to be infused or withdrawn through the proximal end of thecatheter hub. EP 0 268 480 discloses providing the catheter hub with aport extending laterally therefrom. A flexible cylindrical seal extendscircumferentially around the inside the catheter hub in line with theport.

U.S. Pat. No. 5,098,405 concerns a side ported catheter adapter with aone piece integral combination valve. The valve is disposed within a hubof the adapter so as to close the bore of the adapter and the side port.The valve assembly comprises a generally cylindrical body extendingcircumferentially around the interior of the hub in line with the port.The valve assembly further comprises a conical valve element, permittingthe flow of fluid into the catheter from the proximal end of the hub.The device of U.S. Pat. No. 5,098,405 does not permit fluids to beremoved from the patient and only allows fluids to be infused to thepatient through either the proximal end of the adapter hub or the port.

A medical connector is described and shown in WO 96/40359. The connectorcomprises a body having a primary conduit therethrough and a port. Agenerally cylindrical valve is located within the body in line with theport. A tab extends from the valve into the port. The valve is normallyopen, permitting the flow of fluid along the primary conduit. Depressionof the tab in the port closes the valve across the primary conduit,preventing the flow of fluid therealong and allowing fluid to be infusedto or withdrawn from the connector through the port.

Of more relevance, a catheter apparatus with infusion port and valves isdisclosed in WO 2008/052791. The apparatus comprises a hollow catheterextension, the distal end of which can be connected to a catheter. Aconnecting device is provided on the proximal end of the extension. Aport extend radially from the extension and opens into the bore of theextension. A valve assembly is disposed within the extension in linewith the port and comprises a first, generally cylindrical valve elementclosing the port. A second valve element prevents the escape of bloodfrom the extension through the bore in the proximal direction. Thesecond valve element is formed as a two-way valve, so as to permit theflow of fluids in either the distal or the proximal direction.

More recently, WO 2008/052790 discloses a catheter assembly andcomponents thereof. The assembly comprises a valve disposed in thecatheter hub and a valve opener. The valve opener is configured to bepushed by an IV set luer connector to open the valve, to allow fluids tobe passed through the catheter. A tip protector, operable to cover thetip of the needle as the needle is withdrawn from the catheter throughthe catheter hub, may be provided within the valve opener.

WO 2012/009028 discloses a flushable catheter assembly. The assemblycomprises a catheter adapter having a septum disposed therein. A septumactivator is provided to selectively open the septum and allow fluid toflow through the catheter adapter when a coupler is attached to theproximal end of the catheter adapter.

A catheter assembly is disclosed in DE 202007006190 U1.

WO 2004/032995 discloses a method of delivering a local anesthesia and acatheter and needle assembly for use in the same.

A safety shield for a needle is disclosed in WO 2005/042073.

A safety catheter comprising a needle point lock is described and shownin U.S. Pat. No. 5,697,907.

Needle protector devices and assemblies are described in GB 2,343,118.

More recently, WO 2013/016373 discloses a vascular access assembly and asafety device to protect a clinician from accidental needle stickinjuries.

There is a need for an improved catheter assembly, in particular onethat provides for increased control of the infusion and withdrawal offluids to and from the patient through the catheter.

SUMMARY OF THE INVENTION

According to the present invention, there is provided a catheterassembly comprising:

a catheter hub having a chamber therein, the catheter hub having adistal end and a proximal end, the catheter hub being connectable at itsproximal end to a device for the infusion or withdrawal of fluids to orfrom the chamber within the catheter hub;

a hollow tubular catheter having a proximal end and a distal end, thecatheter being connected at its proximal end to the distal end of thecatheter hub, the interior of the catheter opening into the chamberwithin the catheter hub;

a needle having a sharpened needle tip, in a ready position the needleextending through the chamber in the catheter hub and the catheter withthe needle tip extending beyond the distal end of the catheter;

a hollow extension tube having a distal end and a proximal end, theextension tube being connected at its distal end to the catheter hubbetween the proximal and distal ends thereof, the extension tube openingat its distal end into the chamber within the catheter hub, theextension tube connectable at its proximal end to a device for infusingfluid into the chamber within the catheter hub;

a valve assembly disposed within the chamber of the catheter hub, thevalve assembly comprising:

-   -   a first valve member closing the distal end of the extension        tube and openable under the action of a pressurised fluid within        the extension tube; and    -   a second valve member preventing the flow of fluid through the        chamber to or from the proximal end of the catheter hub, the        second valve member being a two-way valve and openable to permit        the flow of fluid through the chamber in the catheter hub in        both a proximal and a distal direction.

The device of the present invention comprises a catheter hub. Thecatheter hub is hollow and has an internal chamber therein, the internalchamber being open at both the proximal and distal ends of the catheterhub. The catheter hub may be formed as a single piece. Alternatively,the catheter hub may be formed as two or more separate pieces connectedtogether.

The catheter hub is formed at its proximal end to be connectable to adevice for infusing fluid into the patient or removing fluid from thepatient, such as a syringe. Such devices are known in the art and willbe familiar to the person skilled in the art. In particular, the innerwall of the proximal end of the catheter hub defining the chamber isprovided with an internal Luer taper, that is a female Luer taper,allowing standard fittings having a standard male Luer taper to beconnected to the proximal end of the catheter hub. The person skilled inthe art will be familiar with the Luer taper standard and itsrequirements.

In one embodiment, the catheter hub comprises a distal hub portion and aproximal hub portion. The proximal hub portion is as hereinbeforedescribed and is connectable to a device for infusing fluid into orremoving fluid from the patient. The distal hub portion may have anysuitable form. In one embodiment, the distal hub portion has a generallyflattened form, such that the catheter hub lies flatter against the skinof the patient and protrudes less from the patient's skin in use. Morepreferably the distal hub portion comprises wing members extending fromopposing sides of the distal hub portion. The wing members increase thestability of the catheter assembly, in particular when the catheter hasbeen inserted into the vein of the patient, and may be used to securethe catheter hub to the skin of a patient, for example by way ofadhesive tape. In this way, movement of the catheter hub and thecatheter is restricted, in turn reducing the occurrence of phlebitis ofthe vein of the patient.

A hollow tubular catheter is connected to the catheter hub and extendsfrom the distal end of the catheter hub.

The catheter assembly further comprises a needle having a sharpenedneedle tip and a bore therethrough. In a ready position, the needle isconnected at its proximal end to a needle hub, as is known in the art,and extends through the catheter hub and the catheter in a readyposition. In the ready position, the sharpened needle tip is distal ofthe distal end of the catheter, allowing the needle and the catheter tobe introduced into a vein of the patient, in known manner. The needlehub preferably has a chamber therein in communication with the bore inthe shaft of the needle, whereby blood flashback in the needle hubchamber may be observed by the user to indicate proper placement of theneedle in the vein, in a known manner. The needle hub chamber istypically plugged at its proximal end with a vented plug that allows airto vent from the chamber, but not blood to flow through the plug.

As the needle tip is withdrawn into the hollow tubular catheter asecondary blood flashback occurs between the outside of the needle andthe inside of the catheter.

A condition for both the primary and secondary blood flashback is thatthe air in the catheter device can be displaced by the blood as the airis vented out of the proximal end of the device.

In one embodiment, the needle is provided with an opening, such as aslot, in the shaft of the needle in the distal end portion of the needleand spaced from the sharpened needle tip. In the ready position, theslot is disposed within the tubular catheter. In use, once the needletip has been inserted into the vein, blood may flow along the bore inthe needle, through the slot and into the catheter around the needleshaft. The blood can then flow from the catheter into the catheter hub,to provide a flashback to the user.

The catheter assembly of the present invention further comprises ahollow extension tube having a distal end and a proximal end. Theextension tube is flexible. The extension tube is connected at itsdistal end to the catheter hub between the proximal and distal endsthereof. Preferably, the distal end of the extension tube is connectedto the distal portion of the catheter hub. The extension tube opens atits distal end into the chamber within the catheter hub, to allow fluidto flow between the extension tube and the internal chamber. Theextension tube is connectable at its proximal end to a device, such as asyringe, for infusing fluid into the chamber within the catheter hub.For example, the extension tube may be provided at its proximal end witha connection hub, preferably a hub having a female Luer taper.

In use, fluid may be introduced into the catheter hub and the catheterby way of the extension tube. By having the device for introducing fluidconnected at the proximal end of the extension tube, it may be locatedaway from the catheter hub and the catheter located in the vein of thepatient. By having the extension tube flexible, movement of the catheterhub and the catheter as a result of the action of connecting ordisconnecting the fluid delivery device at the proximal end of theextension tube is reduced or eliminated. This in turn reduces theoccurrence of phlebitis of the vein in the region of the catheter.

The catheter assembly comprises a valve assembly disposed within theinternal chamber of the catheter hub. The valve assembly, when closed,prevents the flow of fluid between the extension tube and the internalchamber of the catheter hub and the flow of fluid in either the proximalor distal direction through the internal chamber. The valve assemblycomprises a first valve member, which may be opened to permit fluid toflow from the extension tube into the internal chamber of the catheterhub. In this respect, the valve assembly may be a one-way valve betweenthe extension tube and the internal chamber of the catheter hub. Thevalve assembly comprises a second valve member, which may also be openedto permit fluid to be supplied from the proximal end of the catheter hubin the distal direction to the catheter or to allow fluid to bewithdrawn in the proximal direction from the catheter to the proximalend of the catheter hub. In this way, the valve assembly is operable asa two-way valve to control fluid flow through the catheter hub to andfrom its proximal end.

The first valve member controls the flow of fluid between the extensiontube and the internal chamber of the catheter hub. In a preferredembodiment, the first valve member comprises a flexible, resilient valvebody. Under the action of increased fluid pressure in the extensiontube, the valve body yields, opening the distal end of the extensiontube and permitting fluid to enter the catheter hub. The valve body ispreferably a tubular body, in particular disposed within the internalchamber of the catheter hub in contact with the inner surface of thewall of the catheter hub. The valve body and the portion of the internalchamber of the catheter hub in which it is disposed may be cylindricalor, in one embodiment, elliptical, in cross-section.

The first valve member may comprise one or more slits therein, alignedwith the distal opening of the extension tube and for the passage offluid therethrough. If the first valve member has one or more slitstherein, then it can act as a two way valve and blood or other bodilyfluids can be removed through the slits and extension line into asuitable device, such as a syringe or a vacuum collection tube.

The valve assembly comprises a second valve member. As noted above, thesecond valve member controls the flow of fluid through the internalchamber of the catheter hub to and from the proximal end thereof. Thesecond valve member is disposed in the internal chamber of the catheterhub in a position proximal to the distal opening of the extension tubeand the first valve member. In one embodiment, the second valve membercomprises a flexible, resilient valve disc extending laterally acrossthe internal chamber of the catheter hub. The disc is provided with oneor more closable openings, such as slits, therein, in particular one ormore radially extending slits.

The valve assembly may be retained within the internal chamber of thecatheter hub by any suitable means. In one embodiment, the valveassembly is retained by friction between the valve members and the innersurface of the catheter hub. Alternatively, the valve assembly mayengage with one or more recesses or protrusions formed in the innersurface of the catheter hub.

In the ready position, the needle shaft extends through the valveassembly. The second valve member preferably seals around the shaft ofthe needle in the ready position, more preferably in a manner thatallows gas to vent through the second valve member in the proximaldirection, but prevents blood from passing the second valve member. Inembodiments in which the second valve member comprises a disc having oneor more slits therein, this can be achieved by appropriate arrangementof the or each slit, such that, in the ready position, the or each slitis held open by the needle shaft a sufficient amount to allow thepassage of gas but prevent the passage of blood therethrough.

The second valve member may open under the action of a difference influid pressure across the valve member. In particular, the second valvemember may open under the action of an increased fluid pressure on theproximal side of the valve, to allow fluid to be infused into thecatheter and vein of the patient. Similarly, the second valve member mayopen under the action of a reduced pressure on the proximal side of thevalve, to allow fluid to be withdrawn from the catheter and the vein.

In one embodiment, the catheter assembly further comprises a valveopener disposed within the chamber in the catheter hub. The valve openeris disposed within the internal chamber of the catheter hub proximallyof the valve assembly. The valve opener is moveable between a closedposition, in which the second valve member is closed, and an openposition in which the second valve member is open. The valve opener ismoved in the distal direction to the open position by the insertion of adevice into the proximal end of the catheter hub, such as a syringe orother male fitting. The valve opener is urged into the closed positionby the action of the second valve member closing, for example by theresilience of the valve disc. The valve opener preferably has a passageextending longitudinally therethrough and/or around for the passage offluid.

Movement of the valve opener in the distal direction is limited by thevalve assembly. Preferably, means are provided to limit the movement ofthe valve opener in the proximal direction. In one embodiment, the innersurface of the catheter hub is provided with one or more protrusions toengage with the valve opener.

In the ready position, the needle shaft extends through the valveopener. One preferred form of valve opener comprises a stem, having apassage therethrough, and a head portion at the distal end of the stem,having a passage therethrough. In use, a device inserted into theproximal end of the catheter hub contacts the stem of the valve opener,urging the valve opener from the closed position into the open position.As the valve opener is moved distally into the open position, the headportion is urged into contact with the second valve member, opening thevalve assembly.

The stem may comprise a tube, with the needle extending through the tubein the ready position. Alternatively, the stem may comprise one or morelegs extending proximally from the head portion. In one embodiment theregion of the head portion contacting the second valve member isgenerally domed or frusto-conical.

In a preferred embodiment, the catheter device of the present inventionis a safety device and comprises a needle guard assembly. The needleguard assembly acts to cover and block the sharpened needle tip as theneedle is withdrawn from the catheter in the proximal direction andmoved from the ready position into a protected position. In this way,the risk of a needle stick injury occurring is reduced or avoided.

The needle guard assembly may be disposed wholly or partly within theinternal chamber in the catheter hub. In particular, the needle guardmay be disposed within the catheter hub, such that the needle is in itsprotected position with the sharpened needle tip blocked by the needleguard assembly while the needle tip is within the catheter hub. Examplesof preferred needle guard assemblies for use in such embodiments aredisclosed in WO 99/08742. The needle guards of WO 99/08742 are of apassive type, that is the needle tip is blocked by the needle guard asthe needle is withdrawn from the ready position into the protectedposition, without the user having to take any additional actions overand above those required with the use of standard or non-safety devices.Passive needle guards of this type are preferred.

Alternatively, the needle guard assembly may be disposed outside thecatheter hub, in particular proximal of the catheter hub. In onepreferred embodiment, the needle guard assembly comprises a needle guardhousing having a needle guard chamber therein. A needle guard ispreferably disposed in the chamber. The needle guard housing may have aportion extending into the proximal end of the catheter hub. Forexample, the needle guard housing may have a distal end portioncomprising a male taper, such as a standard Luer taper, for engagingwith a female taper in the proximal end portion of the catheter hub.Alternatively, the needle guard housing may reside completely outsidethe catheter hub.

The needle guard assembly is preferably releasably engaged with thecatheter hub. In one preferred embodiment, the needle guard assembly isengaged with the catheter hub with the needle in the ready position.Movement of the needle to the protected position, in which the needletip is blocked, releases the needle guard assembly from the catheterhub.

Most preferably, in the protected position, the needle tip is disposedwithin the needle guard housing and the needle tip is blocked within thehousing by the needle guard.

A needle guard is disposed within the needle guard housing. The needleguards of WO 99/08742 may be employed within the needle guard housing.

One particularly preferred form of needle guard for use in the catheterassembly as hereinbefore described comprises at least one arm, the armbeing moveable from the ready position into a blocking position in whichthe sharpened needle tip is blocked. The at least one arm preferably hasa distal end portion for extending in front of and blocking the needletip in the blocking position. The at least one arm may extend parallelto the needle in the ready position or, alternatively may cross theshaft of the needle in the ready position.

In a preferred embodiment, the needle guard comprises a first arm and asecond arm. One or, preferably both, of the first and second arms maycomprise a distal end portion for blocking the needle tip. The first andsecond arms may extend along opposing sides of the needle shaft in theready position. Alternatively, the first and second arms may intersectand cross the needle shaft in the ready position. As noted above, atleast one of the first and second arms is provided with a distal endportion for blocking the needle tip in the protected position. Inembodiments in which both the first and second arms have a distal endportion, it is preferred that the distal end portions are offset withrespect to one another. In this way, the distal end portions may engageover the needle tip.

The first and second arms may be of the same length or of differentlengths. Preferably, the first and second arms are of different lengths,especially when both arms are provided with a distal end portion. If asingle distal end portion is present, it is preferably disposed on thelonger of the first and second arms.

At least one of the distal end portions is provided with an endmostportion that is curved inwards at its free edge. In this way, it isensured that the needle tip is covered, even if an attempt is made topush the needle guard in the proximal direction, that is back from theprotected position, along the needle shaft. The inwardly curved endmostportion acts to hook onto the needle tip, so as to prevent movement ofthe needle guard in the proximal direction and to prevent the needle tipbecoming exposed.

The needle guard comprising one or more arms may be in the form of aresilient or spring clip needle guard.

In a preferred embodiment, the needle guard within the housing comprisesa needle trap moveable between a ready position, in which the needletrap is held to one side of the shaft of the needle extending throughthe housing, and a protected position, in which the needle trap extendsacross the needle tip and blocks the sharpened needle tip of the needlewithin the housing. The needle guard further comprises a resilient armbiasing the needle trap into the protected position. The resilient armbears against the inner wall of the housing to urge the needle trap intothe protected position. In addition, the needle guard comprises acoupling arm moveable by the needle trap. In the ready position thecoupling arm couples the housing to the proximal end of the catheterhub. Movement of the needle trap from the ready position to theprotected position moves the coupling arm to release the housing fromthe catheter hub.

Accordingly, in a further aspect, the present invention provides aneedle guard assembly for a catheter assembly, the needle guard assemblycomprising:

a housing for receiving a needle extending therethrough and having adistal end and a proximal end, the housing being connectable at itsdistal end to the proximal end of a catheter hub;

a needle guard disposed within the housing, the needle guard comprising:

a needle trap moveable between a ready position, in which the needletrap is held to one side of the shaft of the needle extending throughthe housing; and a protected position, in which the needle trap blocksthe sharpened needle tip of the needle within the housing;

a resilient arm biasing the needle trap into the protected position, theresilient arm bearing against the inner wall of the housing to urge theneedle trap into the protected position;

a coupling arm, in the ready position the coupling arm coupling thehousing to the proximal end of the catheter hub, movement of the needletrap from the ready position to the protected position moving thecoupling arm to release the housing from the catheter hub.

The needle trap may be connected at one end to the resilient arm. In apreferred embodiment, the needle trap is pivotally attached at a firstend thereof to the resilient arm. The resilience of the resilient armmay be provided partly or wholly by resilience in the pivotal connectionbetween the needle trap and the resilient arm. In one embodiment, theneedle trap and the resilient arm are folded together on one side of theneedle shaft when in the ready position, such that the needle trapoverlies the resilient arm.

In the protected position, the needle trap extends distally across thesharpened needle tip, thereby blocking the needle tip and preventing aneedle stick injury. The needle trap may comprise one or more lateralmembers extending in the proximal direction from each side of the needletrap. The lateral members act to retain the needle trap in positionrelative to the sharpened needle tip, in particular preventing theneedle tip from emerging to one side of the needle trap. In use, theneedle trap transitions between the ready position, across the needletip and into the protected position. Further, the needle trap maycomprise a retaining member preventing the needle trap from moving inthe reverse direction, that is towards its ready position, relative tothe needle.

The needle guard further comprises a coupling arm. In the readyposition, the coupling arm engages with the catheter hub, to hold theneedle guard assembly on the proximal end of the catheter hub. In apreferred embodiment, the coupling arm engages with the outside of thecatheter hub, for example with a flange on the proximal end of thecatheter hub. The coupling arm is moved by the needle trap transitioningfrom the ready position to the protected position out of engagement withthe catheter hub, thereby releasing the needle guard assembly from thecatheter hub. In this way, the needle guard assembly is only releasedfrom engagement with the catheter hub once the sharpened needle tip isblocked within the needle guard housing. The coupling arm is preferablyconnected to the needle trap. In one preferred embodiment, the couplingarm is connected to an end of the needle trap, in particular to a secondend of the needle trap opposite the first end. The connection betweenthe coupling arm and the needle trap is preferably pivotal and may be aresilient pivotal connection.

In one preferred embodiment, the resilient arm, the needle trap and thecoupling arm are formed as a single component, with resilient pivotalconnections between the resilient arm and the needle trap and betweenthe needle trap and the coupling arm, the resilient connections biasingthe needle trap into the protected position and the coupling arm out ofengagement with the catheter hub.

The position of the needle trap is preferably stabilised both by thecoupling arm engaging with the wall of the needle guard housing on oneside of the needle shaft and by the resilient arm engaging the wall ofthe needle guard housing on the opposite side of the needle shaft. Inone preferred embodiment, the coupling arm extends through an opening inthe wall of the needle guard housing.

In one embodiment, the coupling arm extends around the needle shaft inthe ready position, preferably within the needle guard housing. In apreferred embodiment, the coupling arm comprises an opening, the needleshaft extending through the opening in the coupling arm in the readyposition.

In the protected position, the needle trap extends distally across thesharpened needle tip and prevents the needle moving in the distaldirection relative to the needle guard assembly. The needle guardassembly further comprises means for limiting movement of the needle inthe proximal direction relative to the needle guard assembly, so as toprevent the needle guard assembly from leaving the distal end of theneedle. The limiting means may comprise a tether, for example extendingbetween the needle hub and the needle guard housing. Preferably, theneedle comprises a bulge, such as a crimp, in the distal end portion ofthe needle shaft spaced from the needle tip. The needle guard assembly,preferably the needle guard housing, comprises a proximal wall having anopening therein, the needle shaft extending through the opening in theproximal wall. The bulge in the needle shaft has a radial dimension thatis larger than that of the opening in the proximal wall, such that thebulge and the distal end of the needle cannot pass through the opening.The region of the proximal wall surrounding the opening may bereinforced, for example by way of a metal ring or washer, to prevent thebulge in the needle shaft being inadvertently pulled through theproximal wall of the housing. This is particularly advantageous when theneedle guard housing is formed from a relatively soft material, such asplastic. In the ready position, the bulge in the needle shaft preferablylies within the hollow catheter. When the bulge is non-circular it hasthe advantage of allowing blood to flow between the inside of thecatheter and the outside of the needle, to provide the secondary bloodflashback.

In a further aspect, the present invention provides an IV catheterassembly comprising a needle guard assembly as hereinbefore described.

BRIEF DESCRIPTION OF THE DRAWINGS

Embodiments of the present invention will be described, by way ofexample only, having reference to the accompanying drawings, in which:

FIG. 1 is a cross-sectional view of a device according to a firstembodiment of the present invention in a ready position;

FIG. 2 is a cross-sectional view of the device of FIG. 1 in thedirection II;

FIG. 3 is a cross-sectional view of the device of FIG. 1 in a retractedposition;

FIG. 4 is a cross-sectional view of a device according to a secondembodiment of the present invention in a ready position;

FIG. 4a is an enlarged cross-sectional view of the needle guard assemblyof the device of FIG. 4;

FIG. 5 is a cross-sectional view of the device of FIG. 4 in a protectedposition;

FIG. 5a is an enlarged cross-sectional view of the needle guard assemblyof the device of FIG. 5;

FIG. 6 is a cross-sectional view of a device according to a thirdembodiment of the present invention in a ready position;

FIG. 7a is a cross-sectional view of a valve assembly for use in thedevices of any of FIGS. 1 to 6;

FIG. 7b is a proximal end view of one embodiment of the valve assemblyof FIG. 7 a;

FIG. 7c is a proximal end of a second embodiment of the valve assemblyof FIG. 7a ; and

FIG. 8 is a perspective view of one embodiment of needle guard for usein the catheter assembly of the present invention.

DETAILED DESCRIPTION

Referring to FIGS. 1 and 2, there is shown a device according to a firstembodiment of the present invention, generally indicated as 2. Thedevice 2 is shown in FIGS. 1 and 2 in a ready position. The device isshown in FIG. 3 in a retracted position, that is with the needlewithdrawn in the proximal direction.

The device 2 comprises a catheter hub 4 having a distal end 6 and aproximal end 8. An elongate, hollow, tubular catheter 10 is connected tothe catheter hub 4 and extends from the distal end 6 of the catheterhub, in known manner. The catheter hub 4 comprises an internal chamber12. The internal chamber 12 is open at the proximal end 8 of thecatheter hub 4 and communicates with the hollow catheter 10 at thedistal end of the catheter hub. Details of the catheter hub aredescribed in more detail below.

A generally cylindrical needle hub 20 has a distal end 22 and a proximalend 24 and a lengthwise axis HA between the distal end and the proximalend. The needle hub 20 is formed with an internal chamber 26, the openproximal end of which is closed by a vented flashback plug 28. In use,the chamber 26 in the needle hub 20 serves as a flashback chamber forthe user to observe blood flashback, again in known manner.

A needle 30 is connected at its proximal end 32 to the distal end 22 ofthe needle hub 20. The needle 30 has a shaft 34 with a bore therethroughand having a sharpened needle tip 36 at its distal end. In the readyposition, shown in FIGS. 1 and 2, the needle 30 extends through theinternal chamber 12 of the catheter hub 4 and through the catheter 10,such that the sharpened needle tip 36 extends beyond the distal end ofthe catheter 10.

The needle 30 can be provided with a slot 38 in the distal end portionof the needle and spaced from the sharpened needle tip 36. In the readyposition, the slot 38 lies within the catheter 10. In use, bloodentering the bore in the needle shaft 34 flows out through the slot 38and between the needle shaft 34 and the inner surface of the catheter 10and provides a flashback indication to the user to indicate that theneedle tip is properly located within a vein of the patient. Bloodflowing through the bore in the needle shaft 34 enters the internalchamber 26 of the needle hub 20 and provides a primary flashbackindication to the user, as mentioned above.

As noted above, the device 2 comprises a catheter hub 4 having aninternal chamber 12. The catheter hub 4 has a proximal portion 40 and adistal portion 42. The internal chamber 12 is open at the proximal end 8of the catheter hub 4 and extends through both the proximal and distalportions 40, 42 of the catheter hub 4, to communicate with the hollowcatheter 10. The proximal portion 40 of the catheter hub 4 is generallyconical in configuration and is formed with an internal taper 44, inparticular a female Luer taper of standard form. The proximal portion 40of the catheter hub 4 is provided with a protrusion 46 extending intothe internal chamber 12 and located distally of the Luer taper. In theembodiment shown in FIGS. 1 and 2, the protrusion 46 is in the form of acircumferentially extending ring.

A valve opener 50 is disposed in the proximal portion 40 of the catheterhub 4. The valve opener 50 has an elongate stem 52 and a conical head 54disposed at the distal end of the shaft 52. A bore extendslongitudinally through the valve opener 50 and receives the shaft of theneedle 30 in the ready position, as shown in FIGS. 1 and 2. The valveopener 50 is retained within the internal chamber 12 of the catheter hub4 and its movement in the proximal direction is limited by theprotrusion 46. The valve opener 50 is free to move in the distaldirection under the action of a male fitting, such as a syringe,inserted into the proximal end 8 of the catheter hub 4.

The distal portion 42 of the catheter hub 4 has a generally flatprofile, as shown in FIGS. 2 and 3, with wing members 60 extending fromopposing sides of the catheter hub 4. The wing members 60 provide ameans for securing the catheter hub 4 to the skin of a patient, forexample by a suitable medical grade adhesive tape.

The proximal and distal portions 40, 42 of the catheter hub 4 may beformed as a single component or may be formed separately and thereafterjoined together in the arrangement shown in FIGS. 1 to 3.

A flexible extension tube 62 extends from the distal portion 42 of thecatheter hub 4. The distal end of the extension tube 62 opens into theinternal chamber 12 of the catheter hub. The proximal end of theextension tube 62 is provided with a hollow connecting hub 64 having aproximal opening and provided with an internal taper, in particular astandard female Luer taper, for accepting a fitting, such as a syringeand the like, in known manner. A vented plug 66 may be provided at theproximal end of the connecting hub 64, as shown in FIG. 1, to maintainsterility. The connecting hub 64 may be used to introduce fluid into theextension tube 62 and the catheter assembly 2, for example by way of asyringe 68, shown in FIG. 3.

The distal portion 42 of the catheter hub 4 is further provided with avalve assembly 70 therein. The valve assembly 70 is disposed within theinternal chamber 12 of the catheter hub and comprises a first valveportion 72, disposed in the internal chamber 12 distal of the valveopener 50, and a second valve portion 74. The second valve portion 74being distal of the first valve portion 72.

The function of the first valve portion 72 is to seal the internalchamber 12 within the catheter hub 4, to prevent the flow of fluids ineither the proximal or distal direction when the first valve portion isclosed. The first valve portion 72 comprises a flexible valve disc 76extending laterally across the internal chamber 12 of the catheter hub4. The valve disc 76 is of a flexible, resilient material. The valvedisc 76 is provided with one or more radial slits therein. In this way,the shaft 34 of the needle 30 extends through the valve disc 76 in theready position, shown in FIGS. 1 and 2. Details of embodiments of thevalve assembly are shown in FIGS. 7a to 7c and described hereinbelow.

With the needle in the ready position, the valve disc 76 closes aroundthe outer surface of the needle shaft 34. With the needle 30 in theready position, the slits are held open a sufficient distance to allowair to vent through the valve disc in the proximal direction, whilebeing sufficiently closed so as to prevent the flow of blood through thevalve disc in the proximal direction. By allowing air to vent throughthe valve disc 76 in this manner, the flow of blood from the slot 38 inthe needle shaft 34 within the catheter 10 along the outside of theneedle is possible, or without the slot 38 in the needle, as the needletip is withdrawn into the hollow catheter tubing, thereby providing thesecondary flashback.

The first valve portion 72 is a two-way valve. With the needle 30retracted and the valve disc 76 closed, the flow of fluid in either thedistal or the proximal direction within the catheter hub 4 is prevented.When there is no valve opener 50, then the valve disc 76 opens under theaction of a reduced fluid pressure on the proximal side of the valvedisc 76, for example by applying a vacuum to the proximal end of thecatheter hub with a syringe engaged with the proximal end of thecatheter hub 4. In this way, fluid may be withdrawn in the proximaldirection through the catheter hub from the catheter 10 to the proximalend 8 of the catheter hub 4. Applying an increased fluid pressure to theproximal side of the disc valve 76, for example by way of a syringeengaged with the proximal end of the catheter hub 4, opens the valve andallows the passage of fluid in the distal direction through the catheterhub. In this way, fluid may be infused to the patient through thecatheter hub 4 and catheter 10.

Engaging a fitting to the proximal end 8 of the catheter hub 4, such asa syringe or the like having a male taper, in particular a standard maleLuer taper, urges the valve opener 50 in the distal direction. Movementof the valve opener 50 in the distal direction causes the head 54 of thevalve opener to contact the valve disc 76 and open the slits in thedisc. Fluid may be withdrawn from or infused to the patient with thevalve open in this manner. The valve disc 76 is formed from a resilientmaterial. As the male fitting is removed from engagement with theproximal end 8 of the catheter hub 4, the valve opener 50 is urged inthe proximal direction by the valve disc 76 until the slits in the valvedisc close. As noted above, further movement of the valve opener 50 inthe proximal direction is prevented by the protrusion 46 in the proximalportion of the catheter hub 4.

The second valve portion 74 is disposed within the internal chamber 12of the catheter hub 4 distal of the first valve portion 72. The functionof the second valve portion 74 is to seal the opening in the distal endof the extension tube 62. The second valve portion 74 is in the form ofa tube 80 of flexible, resilient material extending around thecircumference of the internal chamber 12 of the catheter hub 4. The tube80 conforms to the inner surface of the distal portion 42 of thecatheter hub and provides a fluid-tight seal against the inner surface.The internal chamber 12 within the distal portion 42 of the catheter hub4 may be generally cylindrical, in which case the tube 80 is generallycylindrical. Alternatively, the internal chamber 12 within the distalportion 42 of the catheter hub 4 may be elliptical in cross-section. Thetube 80 for such an arrangement is also elliptical in cross-section.Embodiments of the valve assembly are shown in FIGS. 7a to 7c anddescribed in more detail below.

As noted above, the tube 80 seals the distal end of the extension tube62 at its opening into the internal chamber 12 in the catheter hub 4. Aninterference fit between the tube 80 and the catheter hub 4 urges theouter surface of tube 80 into contact with the inner surface of thedistal portion 42 of the catheter hub, forming a fluid-tight seal.Increased fluid pressure within the extension tube 62 urges a portion ofthe tube 80 away from the inner surface of the internal chamber 12,allowing fluid to flow from the extension tube 62 into the internalchamber 12 and in a distal direction to the catheter 10. In this way,fluid may be introduced into the catheter 10 by way of the extensiontube 62, for example from a syringe 68 connected to the connecting hub64, as shown in FIG. 3.

In order to ensure a distally directed infusion towards the hollowcatheter tubing, the proximal end of the tube 80 may be furtherstiffened by inserting a hard ring at the proximal end of the tube 80just distal of the disc 76 or a flange can be extended from disc 76 thatis held in a groove in the inside surface of the catheter hub. The hardring is shown in dashed lines in FIG. 1, adjacent disc 76, and thegroove of the catheter hub is shown as two spaced apart dashed linefeatures in FIG. 1.

Turning to FIGS. 4 and 5, there is shown an alternative embodiment ofthe device of the present invention. The device of this embodiment,generally indicated as 102, comprises a catheter hub, catheter, needlehub and needle, valve assembly and valve opener, and extension tube ofthe same general configuration as the embodiment of FIGS. 1 and 2 anddescribed above. Features of the embodiment of FIGS. 4 and 5 common tothe embodiment of FIGS. 1 and 2 are indicated using the same referencenumerals.

The embodiment of FIGS. 4 and 5 comprises a needle guard assemblydisposed between the distal end of the needle hub 20 and the proximalend of the catheter hub 4, when the device is in the ready position, asshown in FIG. 4. The needle guard assembly, generally indicated as 120,is shown in the ready position in greater detail in FIG. 4 a.

There can be some overlapping of the proximal end of the needle guardand the distal end of the needle hub and/or overlapping of the distalend of the needle guard and the proximal end of the catheter hub.

Referring to FIG. 4a , the needle guard assembly 120 comprises agenerally cylindrical needle guard housing 122 having a proximal end 124and a distal end 126. Alternative shapes for the needle guard housinginclude a generally rectangular cross-section. The distal end portion isconical in form and provided with a standard taper, in particular astandard male Luer taper. In the ready position shown in FIG. 3, theconical distal end 126 of the needle guard housing 122 extends withinthe female Luer taper in the proximal end 8 of the catheter hub 4.

The needle guard housing 122 comprises an internal chamber 128 open atthe distal end 126 and closed at the proximal end 124 by a proximal wall130. In the ready position, the needle shaft 34 extends through theinternal chamber 128 of the needle guard housing 122 and the proximalwall 130, as shown in FIGS. 4 and 4 a.

A needle guard 140 is disposed within the needle guard housing 122 andcomprises a needle trap 142 having lateral or side members 144 extendingproximally from the needle trap 142. The needle trap further comprises aretaining member 146. When the needle 30 is retracted to the protectedposition shown in FIG. 5, the side members 144 and retaining member 146prevent the needle trap 142 moving laterally relative to the needle andexposing the needle tip.

The needle guard 140 further comprises a resilient arm 150 pivotallyconnected at a first end 152 to the needle trap and bearing on the innersurface of the needle guard housing 122 at a second end 154. In movingfrom the position of FIG. 4a to the position of FIG. 5a , the resilientarm 150 rotates in a first direction, such as clockwise. During the samemovement of the resilient arm 150, the first end 152 of the resilientarm 150 moves radially, as it moves along an arc anchored at the secondend 154, and axially as it moves towards the distal end 126 of thehousing 122.

The needle guard 140 further comprises a coupling arm 160 pivotallyconnected at a first end to the needle trap 142 at a position oppositeto the connection between the needle trap and the resilient arm 150. Thecoupling arm 160 extends from the needle trap 142 across the internalchamber 128 and through an opening 162 in the needle guard housing 122.The coupling arm 160 is provided with a hook 164 at its free end outsidethe needle guard housing 122, which engages with a flange 166 on theexterior of the proximal end 8 of the catheter hub 4, as shown in FIG.4. An opening 168 is provided in the coupling arm 160, through which theneedle shaft 34 extends in the ready position, as shown in FIG. 4 a.

In the ready position shown in FIGS. 4 and 4 a, the needle trap 142 isheld to one side of the needle shaft 34 in a folded position overlyingthe resilient arm 150. The coupling arm 160 is held by the needle shaft34 retracted within the needle guard housing 122, in turn holding thehook 164 engaged with the flange 166 on the proximal end 8 of thecatheter hub 4.

The needle guard 140 is inherently resilient urging the needle guardinto a straight orientation. In the ready position the needle shaft 34holds the needle trap 142 against the inherent bias of the needle guard.When the needle 30 is retracted to the protected position shown in FIGS.5 and 5 a, in particular, when the needle tip 36 is moved to a positionwithin the needle guard housing 122 proximal of the needle trap and thecoupling arm, the resilience of the needle guard 140 urges the needletrap 142 into the blocking position across the needle tip 36. In movingfrom the position of FIG. 4a to the position of FIG. 5a , the needletrap 142 rotates in a second direction, such as counter-clockwise, whichis opposite the first direction. As the needle trap 142 rotates and theresilient arm 150 also rotates, the needle trap 142 also translatestowards the distal end 126 of the housing 122 in going from the positionof FIG. 4a to the position of FIG. 5a . The same movement urges the hook164 of the coupling arm out of engagement with the proximal end 8 of thecatheter hub 4, thereby releasing the needle guard assembly 120 from thecatheter hub. The retaining member 146 is positioned to engage with theneedle shaft at the sharpened needle tip 36 to prevent the coupling armbeing pushed in the reverse direction in the needle guard housing andrealigning the opening 168 in the coupling arm with the needle tip 36.

As shown in the figures, the needle shaft 34 extends through an opening170 in the proximal wall 130 of the needle guard housing 122. The needle30 is provided with a bulge, in the form of a crimp 172, in the distalend portion of the needle shaft spaced from the needle tip 36. In theready position, the crimp 172 is located within the catheter 10. Thecrimp 172 has a diameter greater than the radial dimension of theopening 170 in the proximal wall 130 of the needle guard housing 122. Inthe protected position shown in FIGS. 5 and 5 a, the needle tip 36 iswithin the needle guard housing 122. The needle 30 is prevented frommoving distally relative to the needle guard assembly 120 by the needletrap 142. Further proximal movement of the needle 30 relative to theneedle guard assembly 120 is prevented by the crimp 172 engaging withthe proximal wall 130, as shown in FIG. 5a . A metal washer 174 may beprovided on the inner surface of the proximal wall 130, to engage withthe crimp and prevent the crimp 172 being inadvertently pulled throughthe proximal wall. This allows the needle guard housing 122 to be formedfrom a relatively soft material, such as moulded from plastic.

Turning to FIG. 6, there is shown an alternative embodiment of thedevice of the present invention. The device of this embodiment,generally indicated as 202, comprises a catheter hub, catheter, needlehub and needle, valve assembly and valve opener, and extension tube ofthe same general configuration as the embodiment of FIGS. 1 and 2 anddescribed above. Features of the embodiment of FIG. 6 common to theembodiment of FIGS. 1 and 2 are indicated using the same referencenumerals. The embodiment of FIG. 6 also comprises a needle guardassembly having a needle guard of the same general configuration as thatof the embodiment of FIGS. 4 and 5. Features of the embodiment of FIG. 6common to the embodiment of FIGS. 4 and 5 are indicated using the samereference numerals.

The device is shown in the ready position in FIG. 6. In the needle guardassembly 120 of FIG. 6, the needle guard housing 122 is located whollyoutside the catheter hub 4. The needle guard assembly 120 is coupled toone side of the flange 166 of the proximal end of the catheter hub 4 asin FIG. 4 and described above. To stabilise the needle guard housing 122on the proximal end of the catheter hub 4, the needle guard housing isprovided with an exterior distal arm 210 extending from the distal end126 of the housing on the opposite side to the coupling arm 160. Theexterior distal arm 210 engages with the exterior flange 166 at theproximal end of the catheter hub on the opposite side of the catheterhub to the engagement of the coupling arm 160.

As the needle is retracted to the protected position, the coupling arm160 and its hook 164 are released from the flange 166 of the catheterhub 4. The exterior distal arm 210 is thereby released from engagementwith the flange 166 and the needle guard assembly 120, with the blockedneedle tip 36 therein, may be removed from the catheter hub 4.

Turning to FIG. 7, embodiments of the valve assembly for use in thedistal portion 42 of the catheter hub 4 will now be described.

Referring to FIG. 7a , there is shown a longitudinal cross-sectionalview of a valve assembly for use in the catheter assembly of the presentinvention. The valve assembly, generally indicated as 702, is formedfrom a flexible material impermeable to the passage of liquid and gas.The valve assembly 702 comprises a generally tubular second valveportion 704 and a first valve portion in the form of a valve disc 706 atthe proximal end of the second valve portion.

Views of the valve disc 706 of embodiments of the valve assembly 702 areshown in FIGS. 7b and 7c . The valve assembly 702 may have a generallycircular cross-section, as shown in FIG. 7b . Alternatively, the valveassembly 702 may be generally flattened and have an ellipticalcross-section, as shown in FIG. 7c . The portion of the internal chamber12 within the distal portion 42 of the catheter hub 4 will conform inshape to the valve assembly 702, such that the valve assembly is a tightfit within the chamber and the second valve portion 704 is in closecontact with the inner surface of the chamber, so as to provide a fluidtight seal between the valve assembly and the inner surface of thecatheter hub.

The valve disc 706 is provided with a plurality of slits 708 therein.The embodiments shown in FIGS. 7b and 7c each have an array of threeslits extending radially outwards from the centre of the valve disc 706.Other arrangements of the slits 708 in the valve disc 706 are possible,for example a single slit.

In the ready position, the shaft 34 of the needle extends through thevalve disc 706. The shaft of the needle holds the slits 708 opensufficient to allow gas to pass through the valve disc, in particular inthe proximal direction, but insufficient to allow blood to pass throughthe valve disc. In this way, the user may be provided with a flashbackindication, as described above.

As described above, the valve disc 706 is resilient. In particular, thevalve opener 50 moves in the distal direction against the resilient biasof the valve disc, when acted upon by a male fitting inserted into theproximal end 8 of the catheter hub 4. Upon removal of the fitting, thevalve disc urges the valve opener in the proximal direction, allowingthe valve disc to close and seal the internal chamber of the catheterhub.

As noted above, the needle guard may be of an arrangement that isretained within the catheter hub in the ready position. One preferredembodiment of such a needle guard is shown in FIG. 8. The needle guardis in the form of a needle clip, generally indicated as 802, which ismade of a resilient material, such as metal, having arms 804, 806extending in a distal direction from opposite sides of a proximal wall810. The proximal wall 810 has a hole 812 for the passage of the needle.The needle shaft is provided with a bulge, for example in the form of acrimp, proximal of the tip of the needle as described hereinbefore andshown in the figures. The diameter of the hole 812 in the proximal wall810 of the needle clip 802 is smaller than the maximum transversedimension of the needle at the bulge, so that the needle clip 802 isheld in the protected position on the needle tip by means of the bulge.

In the embodiment shown in FIG. 8, the arms 804, 806 intersect andextend on both sides of the needle and each has at its distal end an endportion 820, 822 which is widened to approximately the width of theproximal wall 810 and which, in the ready position, lies with elasticpretensioning on the outer circumference of the needle. Alternativelythe arms do not have to cross and can extend along opposing sides of theneedle shaft. Upon reaching the needle tip, the distal end portions 820,822 are moved by spring action into the protected position in which thetwo widened end portions 820, 822 engage over and block the needle tip.For this purpose, the distal ends 820, 822 of the arms 804, 806 areslightly offset with respect to one another in the longitudinaldirection or the arms 804, 806 are of different lengths, so that it isthus ensured that the two distal end portions 820, 822 of the armsengage over the needle tip. Alternatively only the longer arm 806 canhave an end portion 822 to block the needle tip. Preferably, the longerarm 806 has an endmost portion 824 curved inward at the free edge, inorder to ensure that the needle tip is covered even if an attempt ismade to push the needle clip 802 back from the protected position on theneedle, the inwardly curved end portion 824 hooking onto the needle tip.The needle clip 802 as a whole can be made very compact and only about 7mm long, for example.

The invention claimed is:
 1. A needle guard assembly for a catheterassembly, the needle guard assembly comprising: a housing for receivinga needle extending therethrough and having a distal end and a proximalend and a lengthwise axis between the distal and proximal ends, thehousing being connectable at the distal end of the housing to a proximalend of a catheter hub; a needle guard disposed within the housing, theneedle guard comprising: a needle trap moveable between a readyposition, in which the needle trap is held to one side of a needle shaftof a needle extending through the housing, and a protected position, inwhich the needle trap blocks a sharpened needle tip of a needle withinthe housing, said needle trap comprising a first end and a second end; aresilient arm biasing the needle trap into the protected position, theresilient arm bearing against an inner wall of the housing to urge theneedle trap into the protected position; and a coupling arm for couplingthe housing to a proximal end of a catheter hub in the ready position;wherein the needle trap and the resilient arm are folded together to oneside of a needle shaft in the ready position; wherein the resilient armis rotated in a first direction relative to the lengthwise axis of thehousing and the needle trap is rotated in a second direction relative tothe lengthwise axis of the housing when the needle trap moves from theready position to the protected position, the second direction beingopposite the first direction; and a lateral or side member extendsproximally from the needle trap, wherein the lateral or side member isconfigured to prevent the needle from moving laterally out of the needletrap; and wherein the coupling arm is attached to the second end of theneedle trap along a line extending generally perpendicularly to thelengthwise axis of the housing.
 2. The needle guard assembly accordingto claim 1, wherein the needle guard housing has a portion for extendinginto a proximal end of a catheter hub in the ready position.
 3. Theneedle guard assembly according to claim 1, wherein the needle trap ispivotally attached at the first end to the resilient arm.
 4. The needleguard assembly according to claim 3, wherein the coupling arm ispivotally connected to the second end of the needle trap.
 5. The needleguard assembly according to claim 1, wherein the needle trap comprises asecond lateral or side member extending in a proximal direction from theneedle trap.
 6. The needle guard assembly according to claim 1, whereinthe needle trap comprises a retaining member preventing movement of theneedle trap from the protected position to the ready position.
 7. Theneedle guard assembly according to claim 1, wherein the coupling armcomprises an opening therein for accommodating a needle extendingthrough the opening in the ready position, and wherein when the needletrap moves from the ready position to the protected position, thecoupling arm is configured to release the housing from a catheter hub.8. The needle guard assembly according to claim 1, wherein the needleguard housing comprises a proximal wall having an opening therein forreceiving a needle shaft extending through the opening in the proximalwall, the opening being configured to engage a bulge on a needle shaftof a needle having a radial dimension that is greater than that of theopening in the proximal wall.
 9. The needle guard assembly according toclaim 8, wherein a region of the proximal wall adjacent the opening isreinforced.
 10. A catheter assembly comprising: a catheter hub having anexterior surface and an interior surface defining an interior cavitybetween a proximal end and a distal end; a catheter tube extending fromthe distal end of the catheter hub comprising a lumen; a needle guardassembly comprising a housing receiving a needle having a needle tip atan end of a needle shaft extending therethrough and said housing havinga distal end and a proximal end defining a lengthwise axis therebetween,the distal end of the housing connected to the proximal end of thecatheter hub and a needle guard is disposed within the housing of theneedle guard assembly, the needle guard comprising: a needle trapmoveable between a ready position, in which the needle trap is held toone side of the needle shaft extending through the housing, and aprotected position, in which the needle trap is rotated and translatedfrom the one side of the needle shaft to a blocking position distal ofthe needle tip of the needle to block the needle tip, said needle trapcomprising a first end and a second end; a resilient arm having a firstend and a second end, the second end of the resilient arm biased by thehousing and the first end of the resilient arm deflects radiallyrelative to the lengthwise axis of the housing in the ready position ofthe needle trap compared to a position when the resilient arm is in theblocking position of the needle trap, the needle trap and the resilientarm being foldable together to one side of the needle shaft in the readyposition; a coupling arm for coupling the housing to the proximal end ofthe catheter hub; and a lateral or side member extending proximally fromthe needle trap, wherein the lateral or side member is configured toprevent the needle from moving laterally out of the needle trap; andwherein the coupling arm is attached to the second end of the needletrap along a line extending generally perpendicularly to the lengthwiseaxis of the housing.
 11. The catheter assembly according to claim 10,wherein the first end of the needle trap is pivotally attached to thefirst end of the resilient arm.
 12. The catheter assembly according toclaim 10, wherein the coupling arm has a first end and a second end andwherein the second end of the needle trap is pivotally attached to thefirst end of the coupling arm.
 13. The catheter assembly according toclaim 10, wherein a portion of the needle guard housing extends into theproximal end of the catheter hub in the ready position.
 14. The catheterassembly according to claim 10, wherein the needle trap has two sidesand an apex therebetween.
 15. The catheter assembly according to claim10, wherein the needle trap comprises a retaining member configured forpreventing movement of the needle trap from the protected position backto the ready position.
 16. The catheter assembly according to claim 10,wherein the needle guard housing comprises a proximal wall having anopening therein, the needle shaft extending through the opening in theproximal wall, the opening is sized to engage a bulge on the needleshaft having a radial dimension that is greater than a diameter of theopening in the proximal wall.
 17. The catheter assembly according toclaim 10, wherein the needle trap, the resilient arm, and the couplingarm are integrally formed as a single component.
 18. A needle guardassembly for blocking a needle tip of a needle, the needle guardassembly comprising: a housing having an exterior surface and aninterior surface defining an interior chamber, a distal end, and aproximal end with a proximal wall having an opening, the housing beingconfigured for receiving a needle in an axial direction through theinterior chamber and the opening on the proximal wall; and a needleguard located within the interior chamber of the housing, said needleguard comprising: a needle trap having a body extending from a first endto a second end, said needle trap movable between a ready position and aprotective position, the needle trap in the ready position being biasedagainst a side of a needle and in the protected position blocking aneedle tip of a needle; a resilient arm having a first end and a secondend, said resilient arm disposed in the interior chamber of the housing,said first end of the resilient arm pivotally connected to the first endof the needle trap to urge the needle trap from the ready position tothe protected position; a coupling arm having a first end and a secondend, said first end of the coupling arm pivotally connected to thesecond end of the needle trap and said second end of the coupling armextending outside of an opening of the housing such that when thecoupling arm couples the housing to a proximal end of a catheter hub inthe ready position, the coupling arm resides radially outside of thehousing; and wherein movement of the needle trap from the ready positionto the protected position moves the coupling arm; and wherein the firstend of the coupling arm is attached to the needle trap at the second endof is changed to the needle trap.
 19. The needle guard assemblyaccording to claim 18, wherein the needle trap rotates when movingbetween the ready position and the protected position.
 20. The needleguard assembly according to claim 18, wherein the coupling arm has anopening between the first end of the coupling arm and the second end ofthe coupling arm for the needle to extend therethrough in the readyposition.
 21. The needle guard assembly according to claim 18, whereinthe coupling arm is attached to the second end of the needle trap alonga line extending generally perpendicularly to a longitudinal axis of thehousing.
 22. The needle guard assembly according to claim 18, whereinthe needle trap comprises one or more lateral members extending in aproximal direction.